Box toe



Patented June 24, 193i) UNITED STATES PATENTS-OFFICE ALBERT L. GLADE, OF IDAHVEBS, MASSACHUSETTS, ASSIGNOR' TO IBECKWITH MANU- FACTURING COMPANY, .01 BOSTON, MASSACHUSETTS, A CORPORATION OF HAS- SACEUSETTS Box tron No Drawing. Original application filed October 81, 1922,.8erial No. 598,214. Divided and. this application filed September 27, 1924. Serial No. 740,414.

1 such stifi'eners may be produced.

Heretofore it-has .been customary in the manufacture of shoe stiifeners such as box toes to form a sheet of fibrous material, usually cotton and wool felt or like open porous material, and then to saturate or impregnate the sheet with a molten mass of a' stiffeningagent in the nature of hydrocarbons, which when cold is hard and friable but which when softened by a relatively moderate degree of heat permits the sheet or blank cut therefrom tobecome'. limp and flexible, so that the box toe blank may be molded about the end of the last in pulling over or. lasting the shoe. 'Varlous stiffening agents have been employed for this and wax.

. Moreiparticularly, the object of the present invention is to produce box toes or the sheets from which the box-toe blanks may be cut, by

purpose, such as resins, gums, as halts ydrocarbons of thenature of ontan incorporating the stiffeningagent with the pulp before manufacture into a sheet on a paper machine so as to render unnecessary the step of separately impregnatin the already formed sheet of fibrous material. It is necessary that the stiifenin agent or agents should'be thoroughly distri uted throughout the sheet, that the should be of such nature that the box toe w en molded is resilient and stiff, that they may be softened so as to render the sheetlimp and flexible when heated to a relatively low temperature, and that they will set quickly when permitted to cool. One

of the prime requisites of the sheet is that it.

must not part or tear easily when the stiffening agent is ina soft plastic condition, and that it may be stretched to some extent and ulled about the toe end of the last without being weakened ortorn so as to conform to the shape of the last without injury.

The present invention consists o a box-toe blank, the 'sheet from which it is cut and a method of producing the same which will provide a box toe having the optimum characteristics which I have hereinbefore referred to.

In initially preparing the sheet, I employ nishing a furnish, including long fibers such as cattle halr, long rope fibers or fiax fibers, and even in some cases may utilize long cotton fibers.

'In addition to these fibers, however, I also employ short fibers, preferably of the character of wood pulp used in the manufacture of paper,-this for the reason that a sheet formed only of long fiber is too open and porous and requires some shorter fiber in order to secure the necessary felting in the formation of the sheet on. the paper machine. Inasmuch as an object which I desire to achieve is to secure a maximum quantity of stiffening agent in the sheet, it is necessar that the fibrous body of which the sheet is ormed should be of such character that it will form properly in a web and yet be sufficiently open to permit the proper discharge of the water from the cylinder in the paper machine. An even web formation is secured by employing both the long fibers "of the nature of cattle hair and short fibers such as obtained in the production of chemical wood pulp or such as obtained from wilLgive to the box toe the necessary stifl'- I ness and resiliency, and which will soften at a relatively low degree of heat and set quickly when cooled. Normally adhesive bituminous materials may likewise be utilized for furthe stiffening agents, provided they be in the form of an aqueous emulsion, so that they may be diluted with water and be thoroughly incorporated with the other elementso' illzgredients of the furnish in the beater s cc As an example, one may proceedv as follows 8 parts by weight of cattle hair or other long fibers and 8 parts by wei ht of sulphate pulp or equivalent short fibrous material may be placed in the beater with a lar e amount ofwater, much more than is or amount of casein dissolved in an alkaline narily necessary for beating the stock. The beating engine is started in operation but the knives are carefully adjusted so as not to cut the fibers but merely to brush them and secure a thorough, physically homogeneous mixture. The stock shouldbethinned withwater as this permits the rapid admixture of the ingredients. Of course, by taking a longer time, one might secure the same results with a thicker stock or one having less water. By having a very thin stock, it is possible to secure the desired physical homogeneity in the course of 15 to 30 minutes. After the beater contents have been brushed as described, the thermo-plastic stiffening agents may now be added. In the example herein given, I employ parts by weight of rosin, 25 parts by weight "of gilsonite and 5'parts by weight of Montan wax, all pulverized to about mesh.

These ingredients are introduced into the.

beater, together with about 30 parts of asphalt-emulsified or dispersed in water. This emulsion or dispersion preferably consists of normally adhesive asphalt emulsified or dis-- persed in water vwith a colloidal clay emulsifying agent, the asphalt constltuting the disperse phase of the emulsion. The amount of the emulsion added to the boaters 1s figured as the asphalt on a dry basis.

An emulsion, such as herein descrlbed, 1s not per se my invention, and can be obtained on open market under the trade name of K-B emulsion. \Vith these hydrocarbon resinous ingred ents, which constitute the thermo-plastic stiffening agent, I preferably add a small solution. Instead of casein, I may use any. other ingredient, which when precipitated by a precipitating agent carries down with it the stiffening materials in a more or less conglomerate-mass. Thus, in lieu of casein,

tage.

formed into a sheet by a cylinder Imay userosin size, viscous animal size, or other equivalent material. In some cases,

- however, I do not utilize. either casein or the sizing material last referred to, but ordithoroughlyf intermixed with thefibrous material in ,th'e beater by continued rotation of the beaterroll adjusted somewhat away from thebedplate, I then add 10 parts by weight of alum as a precipitating agent. The fibIOH Sl jStQCk with i the stiffening agent thoroughly incorporated therein is now aper machine,-'and, when the sheet is of t e desired thickness, it is cut and removed from. the make-up roll. The sheet is then dried for theremoval of water; and, when dry, is relatively open, free and porous with free rosin, gilsonite, Montain wax and asphalt distributed as discrete" particles throughout the sheet,and,when magnified,are-visible as such. \V-llile I still warm frorfithe drier, the sheet is ijzeaeei now preferably passed through calender rolls heated to a suflicient temperature to flux the hydrocarbon stiffening agents so that they will coalesce throughout the sheet. The eflect of the calendering is further to condense and compact the sheet, so that, when the sheet cools, it is relatively hard, compact or dense, stiff and resilient; and it is not alfected by body temperature or materially I may change'the fibrous ingredients by utilizing 5 parts by weight of long fiberssuch as cattle hair, 5 parts by weight of sulphate pulp, and 5 parts by weight of the waste of the final sheet'or waste which is produced from boxtoe material as ordinarily made. In such case, the box-toe waste, which is the residue after cutting out the box toes or other shoe stifi'eners, must be disintegrated before being added to the beater. I find that this disintegration may be accomplished by subjecting the material to the action of an Abbe rotary cutter orgrinder. Such machines are on the market and are easily procurable.

Since there is some tendency of the 'stiflening agents in the waste to gum the knives, I employ as a preventative a small amount of talc which may be thrown into the grinder from time to time by the handful. For example, I find that in any given amount of the disintegrated waste fiber, there need not be over- I of tale to insure the successful operation of'the grinder. Ihe disintegrated Waste material consists of the usual fibers of which the felt was formed together with the gums or solid hydrocarbons with which it was im pregnated. It is possible to reduce the -pro-.

portion of the asphalt emulsion from 30parts by weight to, say, 20 parts by weight, and to increase the percentage'of the casein or other size'which is employed.

By long ;continued experiment, I have found that a sheet,,having only the asphalt emulsion as the stiffening agent, does not produce satisfactory box toes, for the reason that the sheet is too soft and does not possess.

the requisite rigidity and resiliency when cold, and that further it becomes too llmp and ployed in shoe factories in connection with the pulling and lastingop erationsp I re:'

120. soft, when heated in the usual heaters emjected to body'or solar heat. Inasmuch as the hydrocarbons must coalesce and become more-or less amalgamated in the sheet, I'use a certain proportion of Montan wax,-which, 1 because ofits high degree of penetrability, when molten, acts'as'a fluxin agent for the other hydrocarbons 'in the eet. The addition of Montan wax or like hydrocarbon of high penetrability and relatively low-'melt-' ing point is particularly desirable whena tempering agent such as gi'lsonite is employed, as otherwise'iit may be necessary to Q5 heat the calendering rolls to such a high temperature to flux orcoa l'esce the other hydro j carbon ingredients as mightor would tend to burn the. hair or other long fibers employed in making the sheet. "An advantage in employing casein rather than dther'size is that when precipitated with alum it is not affected by dry heat butwill soften when moist. Qrdinarily, in the pulling over or' lasting of shoes, in which stiffened box-toe blanks are 3 employed, it is customary to subject the blank to moist heat,'and therefore it is desirable to use some agent which w en pro-- cipitated-is not affectedby dry heat but which will soften when subjected to heat and mois- 40 ture.

After the sheet is finished, the blanks are ,cutand skived to serve as shoe stifi'eners, such .asrbox toesorcounters.

, The stiflening agents may be referred to as thermo-plastic material, meaning to include by that" term those compounds -or mixtures 'which function as herein set forth,namely those which may be incorporated in the Wet mass of fibrous material While'in a finelydivided condition, which soften on the application of heat not injurious to the shoe, which set rapidly when cooled, which-give rigidity, stiffness and resiliency to the molded box toe,

and which will permit the heated and limp box-toe blank to be stretched about the toe pulling-over and end-g end of the last, in the lasting operations.

Thisis a division of my application Serial.

No. 598,214 filed Oct. 31, 1922, which has matured into Patent No.1, 544,813, granted July 7,1925. 3'. What I claim is:

' 1. A dense, hard and resilient boxtoe comprising'a layer of felted fibers and a thermoplastic material precipitated upon and adherent to the fibers thereof, the content of in excess of the weight of the fibers,"so that said boxtoe is capable of being made limp by moderate heat and of setting rapidly when cooled. p

2. A dense, hard'and resilient box toe comcorporated in and distributed throughout the layera thermoplastic compound and a precipitate for said compound, the content of thermoplastic compound in said box toe being sufficiently high so that it is capable of being made limp by moderate heat" and of settirf rapidly when cooled.

3.- dense, hard and resilient box toe comprising a fiat layer of felted fibers having incorporated in and distributed throughout the layerva thermoplastic compound and a precipitate for said compound, said compound being in a state of coalescence through- .out the said layer and being present in amount suflicient so that said box toe is capable of beingrnade limp by moderate heat and 0 setting .rapidly when cooled.

4. A hard dense compact resilient box toe consisting of felted fibers, a thermo-plastic stifiie nin'g compound in amount inexcess of thermoplastic material in saidboxltoe being 1 prising a flat layer of felted fibers having inv the weight of the fibers so as to render said box toe'capabl'e of being made limp by mod erate heat, and a precipitate, said fibers comprising both long and short fibers, so that' i when said box toe isheated it may be stretched about the toe of a last without tearing, said thermo-pla'stic stilfeningcompound beingof awcharacter to soften at low heat and'to setv rapidly when cooled, andsaid' precipitate being of such character as to soften; when subjected to heat and moisture. 1

'5. A. dense, hard and resilient box toe, "com: prising a sheet composed of interfelted fibers, and thermoplastic material prepond-- crating in amount over such fibers precipitated upon and adherent thereto and present in amount suflicientso that said box toe is capable of-bei'ng made limp by moderate heat I and of setting rapidly when cooled.

.6. A dense, hard and resilient box toe,

comprising a sheet composed of long and short fibers interfelted'. in approximately equal proportions, and thermoplastic material preponderating in amount over such fibers precipitated upon and adherent there-' to and present'in amount suflicient so that said box toe is' capable of being made limp by moderate heat and'of setting rapidly when.

cooled.

In testimony whereof I have aflixed my 1 signature.

' ALBERT L. CLAPP. 

